Judge whether the following statement is correct or incorrect and provide a clear explanation. (a) "The global minimum variance portfolio in the Markowitz portfolio selection remains unchanged if more securities are added to the investment universe." (3%) (b) "Under the market equilibrium, a zero-beta portfolio must be less risky than the market portfolio (M),." (3%) (c) "Under the market equilibrium, there must be no inefficient asset in our stock market." (3%) (d) "The assumption of risk aversion is required to derive CAPM and APT. (e) If prices reflect all public information, actively managed mutual funds should not be able to outperform passive strategies."